UVA 11806 repulsion principle + binary

It's easy to think of the principle of repulsion, and here's a little trick of using a binary number to represent the intersection of a set.

1#include <iostream>2#include <cstring>3#include <cstdio>4 using namespacestd;5 6typedefLong Longll;7 Const intMOD =1000007;8 Const intN =501;9 intCn[n][n];Ten  One voidInit () A { -Memset (CN,0,sizeof(CN)); -cn[0][0] =1; the      for(inti =1; i < N; i++ ) -     { -cn[i][0] = Cn[i][i] =1; -          for(intj =1; J < I; J + + ) +         { -CN[I][J] = (Cn[i-1][J] + cn[i-1][j-1] ) %MOD; +         } A     } at } -  - intMain () - { - init (); -     intT; inCIN >>T; -      for(int_case =1; _case <= t; _case++ ) to     { +         intN, M, K; -CIN >> n >> M >>K; the         intAns = cn[n *m] [K]; *          for(ints =1; s < -; s++ ) $         {Panax Notoginseng             intCNT =0, r = N, c =m; -              for(inti =0; I <4; i++ ) the             { +                 if(S & (1<<i)) A                 { thecnt++; +                     if(I &1 ) -                     { $r--; $                     } -                     Else -                     { thec--; -                     }Wuyi                 } the             } -             if(CNT &1 ) Wu             { -Ans = (Ans-cn[r * c][k] + MOD)%MOD; About             } $             Else -             { -Ans = (ans + cn[r * c][k])%MOD; -             } A         } +cout <<" Case"<< _case <<": "<< ans <<Endl; the     } -     return 0; $}

UVA 11806 repulsion principle + binary